下列材料中()属于难加工材料。
A.45号钢
B.40Cr
C.Q235
D.1Cr13SiAl
参考答案:D
孕妇用氯霉素,可能会引起胎儿()孕妇用氨基糖苷类药,对胎儿的影响是()
A.第八对脑神经及肾受害
B.出现灰婴综合征
C.溶血,导致发生肝损害及核黄疸
D.产生新生儿血小板减少症
E.青少年期发生 * * 腺病及阴、道与宫颈透明细胞癌
I must have been a great _____ to my parents in those hard days, for I never failed to live up to their
expectations.[ ]
A. achievement
B. comfort
C. disappointment
D. support